John J. Sweeney is to retire this month after 14 years but plans to keep active in worker issues. With a pro-labor president and a Democratic-run Congress, he says it's a good time to step down.

He came to power as an insurgent vowing to shake up the stodgy House of Labor that was the AFL-CIO.

Fourteen years later, John J. Sweeney, an immigrants' son who rose to the pinnacle of U.S. unionism, is stepping down this month as president of the AFL-CIO.

The labor movement remains deeply divided, its ranks greatly thinned, its top legislative goals unrealized and unemployment nearing 10%, the highest in more than a quarter of a century. Yet Sweeney, 75, departs as organized labor faces its best prospects in years.

"It's a good time for me to wind down," said Sweeney, his low-key, parish-priest demeanor belying a militant commitment to labor. "It's time for a change."

The election of a pro-labor president and the Democratic takeover of Congress -- both achieved with strong union backing -- have provided a propitious moment for Sweeney to exit center stage in the movement that has been his life for more than half a century. Rebuilding the middle class through union membership, labor's longtime mantra, now has the presidential imprimatur.

These days, Sweeney is a frequent guest at the Obama White House. By contrast, during the Bush administration, he was invited only once in eight years -- and that was at the Vatican's initiative, during a papal visit.

Sweeney's likely successor is a close ally, Richard L. Trumka, 60, the former United Mine Workers president and the current No. 2 at the AFL-CIO, whose 56 affiliated unions represent roughly 9 million workers.

Trumka is widely expected to carry on Sweeney's strategies, although the trained lawyer will probably assume a higher public profile than Sweeney, never a noted orator. Sweeney's departure comes at a crucial juncture. Labor is desperately seeking to reverse a decades-long decline that has seen the percentage of the nation's workforce that is unionized plummet almost 50% since the mid-1970s to about 12.5% today, experts said.

Despite the bleak scenario, last year's national elections and a recent uptick in union representation -- especially in California -- have provided cause for optimism.

"He's stepping down with labor on the rebound, in a way that hasn't been the case of predecessors in previous transitions," said Joseph McCartin, a labor historian at Georgetown University.

Indeed, Sweeney came to power in 1995, at a time of bruising turmoil.

He led a dissident ouster of Lane Kirkland, who had carried on the Cold War-tinged leadership of his steely predecessor, George Meany. Sweeney's New Voice slate pledged to transform what many viewed as a moribund federation alienated from contemporary working America and its fast-shifting economics and demographics.

"Sweeney repositioned labor as best he could, and with considerable success, at the center of American liberalism," said Harold Meyerson, editor at large of the American Prospect, a liberal monthly in Washington, D.C., and an occasional contributor to the Los Angeles Times.

Many credit Sweeney with reinvigorating union-organizing efforts, ratcheting up the federation's grass-roots political operation and reaching out beyond its traditional white male base.

"He has left a legacy of modernizing the AFL-CIO and bringing in new workers who historically weren't very central to it, including women, immigrants and more generally people of color," said Ruth Milkman, a labor expert at UCLA. "And he put organizing back on the center stage."

Sweeney helped reverse much of organized labor's traditional antagonism toward immigrants, long viewed as a hard-to-organize bloc that drove down wages.

It was fitting, then, that Sweeney, the Bronx-born son of working-class Irish immigrants, ventured to a blazing Hollywood street corner last month to express solidarity with struggling carwash employees engaged in a bitter organizing battle. Afterward, he bantered with the carwasheros and their allies.

But the long battle ahead for those who toil in L.A.'s carwashes only mirrors the barriers that face the labor movement, however invigorated it may be.

Labor's No. 1 legislative priority, the Employee Free Choice Act, which would ease the way for union organization, faces an uncertain future. Business has mounted a massive, costly campaign to derail the measure, labeling it a power grab by "labor bosses," Sweeney prominent among them.

"Unfortunately, Mr. Sweeney had a tendency all these years to vilify today's employers in a way more consistent with the 1930s than the modern-day workplace," said Randel Johnson, senior vice president of the U.S. Chamber of Commerce. "That hard rhetoric made it difficult for us to work together on anything. . . . I think that accounts for more defeats for labor than victories."

The future of healthcare reform, another labor priority, is also in doubt.